Example embodiments described herein relate to methods and systems for communicating with storage devices using slim IP stacks.
Communication protocols (e.g. Transmission Control Protocol/Internet Protocol (TCP/IP) and protocols based on the Open Systems Interconnection basic reference model (OSI model)) are configured specifically for networking applications including the Internet. Such protocols are often developed with a single purpose in mind, specifically network communication. Applications may communicate over a network using different communication protocols. Besides there being a wide array of applications and protocols, the network hardware (e.g. receivers, transmitters, and cables) can differ from device to device. The OSI model utilizes a multi-level scheme to provide a flexible solution that accommodates all such variation with a standard interface.
Because each protocol module usually communicates with two other modules, the modules are commonly referred to as “layers” in a stack of protocols. In the OSI model, there are seven layers. The layers are: application, presentation, session, transport, network, data link, and physical. A layer is a collection of related functions that provides services to the layer above it and receives service from the layer below it. The lowest layer (known as the physical layer) always deals with low-level, physical interaction of the hardware. Every higher layer adds more features. User applications usually deal only with the top-most layers (known as the application and presentation layers in OSI).
The TCP/IP reference model consists of four layers (application, transport, internet, network access). The network access layer may be thought of as a “bundling,” of the network, data link, and physical layers in the OSI model, and the application layer may be thought of as a “bundling” of the application and presentation layers in OSI. An example of the layers in a TCP/IP implementation for accessing the Internet, in top-down hierarchy, is as follows:
(1) ethernet and R45/CAT5 (network-access layer):
(2) IP commands (internet layer);
(3) TCP commands (transport layer); and
(4) web browser commands such as http (application layer).
TCP/IP enables features that currently are not supported by logical block addressing (LBA) architecture typically used to access storage devices. However, TCP/IP (and communication protocols based on OSI) is mostly suited to communication between applications executed from different systems (e.g. different operating system and hardware) to communicate with each other in a standard way. Furthermore, extensive modifications to LBA architecture and associated applications are necessary in order to employ LBA as a standard in security and communication applications between client and server applications, for example.
Storage devices that utilize LBA architecture (e.g. file system and block device driver) provide a standard command for retrieving information from the storage device (e.g. vendor ID/name). Such a configuration only partially solves the problem of obtaining the properties (e.g. security and compression properties) of the storage device, since the storage device is limited to export only standard capabilities, not proprietary ones. Implementation of TCP/IP in storage-device architectures has not been utilized in the art for such data-access applications.
Network chip developers have implemented the full TCP/IP stack as hardware components. Furthermore, simple tasks that do not require the full TCP/IP stack have been handled by reduced stacks in which the upper layers are not implemented. Examples of tasks using such implementations include the “ping” operation in which only the network-access layer is needed, and the User Datagram Protocol (UDP), a broadcast protocol that uses only the three lower layers of a standard TCP/IP stack (i.e. network-access, internet, and transport layers). Such approaches are not capable of handling applications that require the use of the application layer of the standard TCP/IP stack.
It would be desirable to have methods and systems for communicating with storage devices using slim IP stacks.